Evil bay sells them loose. Space the using a socket/washers as per Flags comment. Using the correct size bolt should compress the rivetnut and hopefully extract the bearing.
Alternatively a collet type of bearing puller(hire/ buy) should do the job.
Just my suggestion 

Thank you for the split collet puller suggestion. I think that's the way to go.

Use collet type of pullers at work to pull small, blind bearings. Definitely work 

Use collet type of pullers at work to pull small, blind bearings. Definitely work 

Need one that does 8mm. Seen a set for 33 quid on fleabay - wonder if it's up to it?

Would something like this work?   

http://www.ebay.co.uk/itm/Blind-Hole-Inner-Bearing-Puller-Set-Slide-Pilot-Needle-Hammer-Internal-Kit-9PC/263232534145?epid=2271136530&hash=item3d49e1b681:g:YF4AAOSwFyhZ7zrf

Dave,

That's the sort of kit I'm on about👍

Would something like this work?   

http://www.ebay.co.uk/itm/Blind-Hole-Inner-Bearing-Puller-Set-Slide-Pilot-Needle-Hammer-Internal-Kit-9PC/263232534145?epid=2271136530&hash=item3d49e1b681:g:YF4AAOSwFyhZ7zrf

Thanks Dave.  That's the one I saw but you've found it 4 quid cheaper! Cheers mate. Going to order it now

You can expand rivnuts using a long bolt, as I have no photo from the bolt head down. A nut to compress the thing, under that a flat washer or 2 then an oversize nut that does not grip the thread then another washer or 2 then the rivnut. You need to hold the bolt head and larger nut still and turn the top nut down to wind the rivnut up.

Have fitted loads without a tool the smaller they are the easier they crimp.

See Mark, RIVNUTs

Daily Mail will spot this and have them curing disease next

Re your question about the screw removers, I have been away a few days and wrote a long detailed reply on my phone then lost it. In a nutshell they may work on phosphor bronze but not on ball bearings with an inner race that turns.
Main thing to be careful of is smashing them and leaving the outer race in place.  It is made of extremely hard metal pressed into a soft metal so a bugger to break out.  Strongly recommend warming the thing while using the puller (whichever you finally choose)

Good luck
Dave

See Mark, RIVNUTs

Daily Mail will spot this and have them curing disease next

Re your question about the screw removers, I have been away a few days and wrote a long detailed reply on my phone then lost it. In a nutshell they may work on phosphor bronze but not on ball bearings with an inner race that turns.
Main thing to be careful of is smashing them and leaving the outer race in place.  It is made of extremely hard metal pressed into a soft metal so a bugger to break out.  Strongly recommend warming the thing while using the puller (whichever you finally choose)

Good luck
Dave

I wondered how long it would take you! 

The answer is ridiculously simple and obvious after looking in the book.

You have a spindle and bearing out, so bearing in vice and knock spindle out.

Refit spindle into carb to drive the other bearing out.

You have everything you need to do the job in the carb apart from a vice,  hammer and punch.

The answer is ridiculously simple and obvious after looking in the book.

You have a spindle and bearing out, so bearing in vice and knock spindle out.

Refit spindle into carb to drive the other bearing out.

You have everything you need to do the job in the carb apart from a vice,  hammer and punch.

Thanks Snoopy. Anyone want to buy a split collet bearing puller? 

Just unfortunate we were away on a cruise for 2 weeks can you return it as unsuitable and get a refund.

Just unfortunate we were away on a cruise for 2 weeks can you return it as unsuitable and get a refund.

I'll try. Ebay and I think it came from China 

Snoopy, as usual you're a star. I hadn't realised there was a shoulder on the spindle until Farmer Rob pointed it out to me when I was there last week. Even then I didn't think of getting the bearing out this way. Worked a treat - one tap of the hammer and out they came!

Also have managed to return the puller - just cost £3 postage. Phew!

That's a pint I owe you

Glad to read it worked out well in the end.